Fredde cup holder

OK, so this is a fairly specific utilitarian thingy... I just got a new desk from IKEA, and they named it "Fredde." This desk has 2 cup holders built in, but while I found them fine for a can or bottle, I like to drink ice water from a large plastic pint glass. So I needed a larger cup holder. Rather than cut the holes in the desk, I just made a bi-level cup holder to fit my larger cup.

Update 7 November, 2016: Added "standard" version of cup holder by request.
Update 6 April, 2017: Added v2 and v3 versions, differences noted below.

Some stats, based on v1 file:
Cupholder cutout diameter in desk: 80mm
Inner diameter of original cup holder: 72mm
Inner diameter of 2nd level of new cup holder: 93mm

(v1) This cup holder is probably less than 1mm from being a "snug" fit in the hole. As it is, it has very little wiggle, so it is quite stable.

(v2) Added horizontal ribs on the upper ledge where a larger cup or mug rests, to lift the cup off the surface & reduce the chance